Resolving the age and chemical abundance ratios of a quiescent galaxy at z 2

Measuring the chemical composition of galaxies is crucial to our understanding of galaxy formation and evolution models, but it is extremely challenging for quiescent galaxies at high redshifts. These galaxies have a relatively faint stellar continuum, making it difficult to measure absorption features, and their compact sizes make it even more difficult to spatially resolve the stellar populations. However, gravitational lensing offers the opportunity to study these galaxies at the highest resolution possible. In this work, we analyze the integrated and resolved spectra of MRG-M0138, a lensed quiescent galaxy at z = 1.98 which is the brightest of its kind at z~2 with an H-band magnitude of 17.1. Taking advantage of both Lick index fitting and full spectral fitting, we have measured the stellar age and abundance ratios, including [Mg/Fe] and [Fe/H], as well as radial variations in these quantities to understand star formation history and formation timescale of this galaxy. MRG-M0138 is only the second individual z~2 galaxy for which stellar chemical abundances have been measured. We will discuss implications of our measurements for understanding star-formation quenching in massive galaxies and for local stellar archaeological approaches.